CDROM:The cheapest CD transport with great sound

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Pardon my intrusion, but those pretty looking ROE gold capacitors are "slow" sounding when used in analog cirucits. They are also ancient and long discontinued and probably dried out. If they power any of the digital parts on this board I think they would be a bad choice becuase their long body and leads are probably picking up noise. OSCON SEPC would be much better here. You can buy them at RS these days, and they dont cost much.

My suspicion is that putting that DAC in a shielded chassis may help your situation.
 
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The Blu-ray has a slower rise time and bags of jitter..
I noticed, but I bought it because it was just called it an excellent product
Panasonic DMP-BDT500 Blu-ray player review - Blu-ray Players

Except that the CDROM seems to show one abnormally narrow pulse of about 50ns just to the left of the zero line..
I had not seen this !!!
tonight I measure again, I hope that was not caused by my mistake with the oscilloscope

@ erin
- I tried to convert the SPDIF in I2S using a card with additional WM8804 without solving

ra6c1s.jpg


- invaluable advice, will be one of the next things I'll do

- OT - because after writing and sent to the forum, spends a lot of time before you see the answer ??
 
@scopeboy
as I imagined I must have done something during the measurement to generate that error,
I repeated four times without there being the same view
2ii7vw6.jpg

is not this the reason for the interruption in the audio signal
:( :( :( :(

Pardon my intrusion, but those pretty looking ROE gold capacitors are "slow" sounding when used in analog cirucits.
I believe not be exceptional, but for now I would like to first solve the problem without making changes

My suspicion is that putting that DAC in a shielded chassis may help your situation.
Tomorrow I will try to shield the card with a metal roof, hoping that something changes
 
@erin
Unfortunately not!

I covered with the carcass of an old CDrom
is connected to the ground of the supply
An externally hosted image should be here but it was not working when we last tested it.

right in photo
same result .......

@marce
the CDrom is powered (+5V +12V) with two stepdown 2A with LM2596S with added 4 4700uF capacitors, checking with the oscilloscope will not notice noise or fluctuations

I'm going crazy !!!
 
The noise on the flat sections of the square wave is either high frequency noise on the supplies or being picked up by either the scope probe or some of the system wiring, you get this during EMC tests when the electronics are not screened properly or during conducted susceptibility.
 
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